In communication networks, such as telecommunication networks, a call or a service often involves, on the one hand, a control plane or signalling plane and, on the other hand, a user plane or media plane. The control plane or signalling plane is concerned with connection management. The user plane or media plane is mainly in charge of transporting the user data.
In this context, network operators often want to define and enforce a set of rules in the network. A set of rules constitutes policies. A policy framework for managing and enforcing these policies usually includes at least three elements, or functions: a policy repository for storing the policy rules, which may be user-specific, a policy decision element, function or point, and a policy enforcement element, function or point. The purposes of a policy framework include controlling subscriber access to the networks and services.
A policy framework notably addresses the decisions as to whether the subscriber, i.e. the user, is entitled, or authorized, to enjoy a service, and whether the network can provide the service to the subscriber (and, possibly, with which quality of service).
Policy and charging control (PCC) architectures, such as, but not limited to, the architecture described in “3GPP TS 23.203 V12.3.0 (2013-12); Technical Specification; 3rd Generation Partnership Project; Technical Specification Group Services and System Aspects; Policy and charging control architecture (Release 12)” (available from http://www.3gpp.org/ftp/Specs/html-info/23203.htm) (hereinafter referred to as reference [1]), integrate the policy and charging control.
In such a PCC architecture, the policy and charging rules function (PCRF) is a functional entity in charge of deciding charging, policies and quality of service (QoS) for services of a given user. The PCRF may for example decide the quality of the connection to be allocated for voice, video, etc., which results, for example, on the establishment of dedicated bearer(s) with guaranteed bit rate (GBR) or non-guaranteed bit rate (non GBR). The PCRF may also make decisions about packet forwarding treatment in the radio access network (RAN) by means of determining the QoS class identifier (QCI). The PCRF may also decide, at the packet core control plane, the priority of a bearer to be established over other bearers, for the same or different users. Based on the above decisions by the PCRF, control rules may be generated and then installed in a policy and charging enforcement function (PCEF) and a traffic detection function (TDF) of the PCC architecture, so that each service is given the appropriate treatment that the service requires. In particular, the control rules installed in the PCEF are the so-called PCC rules, whereas the control rules installed in the TDF are the so-called application detection and control (ADC) rules. Installing PCC rules from the PCRF in the PCEF may include the PCRF generating the PCC rules, downloading and activating said PCC rules to the PCEF, or may include activating, from the PCRF, indicated PCC rules configured in the PCEF. Likewise, installing ADC rules from the PORE in the TDF may include the PCRF generating the ADC rules, downloading and activating said ADC rules to the TDF. Notwithstanding this, where a PCEF is enriched with TDF capabilities, such PCEF only handles PCC rules, and at least some of these PCC rules may include ADC rules information usable by the TDF capabilities.
It is desirable to improve PCC architectures and similar architectures, notably by facilitating the provisions of services to users, taking into account the requirements associated with specific situations. This should preferably be achieved without increasing, or at least without excessively increasing, the implementation and architecture complexity and the associated equipment costs. It is also desirable for network operators to be able to reliably provide services and service components to users, while taking into account the potential need to subject the traffic associated with a service or a service component to a special treatment, such as for example special contents delivery.